I have a GL1500 1998 CSC Trike. The other day, I rode for about an hour and parked it for several hours. When I went to get back on, it would not start. Everything looked like it should, but no power. I put it on trickle charge and about 36 hours later, tried it and nothing. Does anyone have any ideas why?

I suspect a little more detail on the description of the problem will help. When you say there's "nothing", do you mean there's no lights, no ignition lights, no horn, etc., or do you mean that it won't crank? Or, does it crank but not start?

If there is, indeed, absolutely nothing, I'd suspect either the battery cable connections, or the ignition switch. The latter is easy enough to check - switch it on & off about 100 times, and see what happens. If you get anything during this, then the switch is suspect.

I turned the radio down and pulled the 94 1500 into the garage after a few hour ride. Let the bike sit a couple of days before going out and discovering the dash wouldn't light up when key turned on! Trusty HFT multimeter says 4 volts, hmmmm, Attach battery tender and watch volts over the next several hours
Didnt want to jump start the bike and throw 60 amps from the compufire alt at a low charge AGM battery
Word is never let agm go dead!

Engine started on its own with 13.5 showing and batt read 14.5 immediately- indicating the alt is functioning
left it on the tender and its green dot lit now

Narrowing down the search of potential typical problem spots = I finally found the source!
Who has guessed it by now??
Turned radio DOWN- not OFF, flipped the kill switch and turned the key off far enough for headlight to go off, get off the bikeOOOOPS
Seems there is still power for the radio if you forget to turn it OFF and DONT remove the key from ignition,,maybe leave it on aux??
the radio volume was on but not enough to be heardLessons to Learn,, every-day!!

Mine took overnight on the battery tender using less than 2 amps charge rate and the other fancy stuff it does- till the green light indicating `full` came on
So far the battery seems ok, a good test ride will confirm
As long as we don't get to totally dead on the AGM style- it should be ok now

Info for those new to battery charging (not trying to talk down to anyone here = I write an acura tech forum for people who never opened the hood before)
If using a conventional wet cell battery that you can fill/top off when needed, make sure there is sufficient fluid level in each cell before chargingCenter cell got low and killed 2 batts on my shadow till I went agm for it too
Add distilled, not tap- water, but not to the upper fill mark- it will rise as it charges
leave caps sitting loosely over holes to allow venting
Top off fluid level as needed after charged, install caps, ck all connections and clean the ground wire contacts
Watch the min max lines on side of battery when filling!

If using the $5 HFT maintainer, throw it in the trash! get a real battery tender that knows to stop charging~ guess how I know

Note: Keep the battery charger unit below the level of the battery, avoids explosions in garage!
Note: even the good brands of small battery maintainer/chargers don't actually recharge a battery to full-full
A 30-60 minute ride letting the alt top off the battery is the best to finish the job

I think that I will have to replace the ignition switch. I tried it again after 48 hours and the only indication I got was a flashing clock on ACC. after about 50 on & off cycles. Still wouldn't start. Anyone know the steps to replace the switch? Also, I would like a repair manual for my Goldwing. Any ideas?

a Clymer repair book will get you thru most things.
I would start with the DIY section on this forum- its excellent Broken down by engine size!
and another Wing specific forum found using search engine will have similar diys

If stuck, go to the thread boards like this one and search, if not =post your problem!
Ign switch seems like an item found in the DIY.
Disconnect battery NEG, remove screws from ign switch surround, trace wiring to least accessible place... and find connectors!

I've been taking close up pics of bike projects with the cell phone, Flash ON, and point in the general direction of places you cant see inside the cowling or engine.
With that bright light and ability to enlarge view and move thru the pic = you can find hidden wire clips, screws, who knows

Did you ck battery voltage after all the charging?
Before the switch goes under the knife, a good battery has to be in there
You may have a bad cell in the old battery, wont take a charge and wont run the bike = shorted internally
How were the fluid levels? or is this an AGM type battery

Didn't check voltage, but will. I put a new battery in last September, the reason I thought it may be switch, after riding it just would not show anything(clock flashed, no indication on gauges, no lights, no start). Thanks for the reply, I will check the battery and find the manual you suggested.

A trickle charger is NOT what you use for charging a dead battery. You need a proper charger.

Come back with your battery Voltage. Don't jump onto something else without eliminating the first one. Don't just go jumping from item to item, and hope it fixes the problem.

Take your working car, and with it turned off, try to jump start your bike. Then come back with what happens when you do what. It could just as easily be bad connections, positive and ground, on the bike. There is no guarantee that your 1 year old battery is still good. All signs show no voltage, not a problem with your switch.

The service manual should have the step-by-step to trace down the problem.